package com.atguigu.gulimall.product.service.impl;

import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1、查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2、组装成父子的树型结构

        //2.1)、找到所有的一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter((categoryEntity -> {
            return categoryEntity.getParentCid() == 0;
        })).map((menu) -> {
            menu.setChildren(getChildren(menu, entities));
            return menu;
        }).sorted((menu1, menu2) -> {
            return (menu1.getSort() == null ? 0:menu1.getSort()) - (menu2.getSort() == null ? 0:menu2.getSort());
        })
        .collect(Collectors.toList());


        return level1Menus;
    }

    private List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all){
        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
            return categoryEntity.getParentCid() == root.getCatId();
        }).map(categoryEntity -> {
            //1、找到子菜单
            categoryEntity.setChildren(getChildren(categoryEntity, all));
            return categoryEntity;
        }).sorted((menu1, menu2) -> {
            //2、排序
            return (menu1.getSort() == null ? 0:menu1.getSort()) - (menu2.getSort() == null ? 0:menu2.getSort());
        })
                .collect(Collectors.toList());
        return children;
    }

    @Override
    public void removeMenusByIds(List<Long> asList) {
        //TODO 1、检查当前删除的菜单，是否在其他地方引用

        // Mybatis-plus支持逻辑删除
        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> pathList = new ArrayList<>();
        List<Long> parentsPath = findParentsPath(catelogId, pathList);
        Collections.reverse(parentsPath);
        return parentsPath.toArray(new Long[parentsPath.size()]);
    }

    private List<Long> findParentsPath(Long catelogId, List<Long> pathList){
        pathList.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if (byId.getParentCid() != 0) {
            findParentsPath(byId.getParentCid(), pathList);
        }
        return pathList;
    }
}